/Engine/Source/Editor/UnrealEd/Public/EditorViewportClient.h
Called when the user clicks in the viewport
virtual void ProcessClick ( [FSceneView](API\Runtime\Engine\FSceneView) & View, [HHitProxy](API\Runtime\Engine\HHitProxy) * HitProxy, [FKey](API\Runtime\InputCore\FKey) Key, EInputEvent Event, uint32 HitX, uint32 HitY )